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Help Us Keep an Eye on Climate Change

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Detailed Description

Attention citizen scientists: We need your help watching the way the world changes!

For nature, timing is everything. So how does climate change affect the timing of things like flowers blooming and animals migrating, and why is this so important?

Learn more, and find out how YOU can help us by observing the world around you from USGS scientist Jake Weltzin, Director of the National Phenology Network.




Public Domain.



[Intro Music]


Catherine Puckett: Hello and welcome to USGS CoreCast. I'm Catherine Puckett.

I have a question for you listeners. How would you like to be a "citizen scientist" and help us keep an eye on climate change? Interested? Listen up.

I'm talking today with Dr. Jake Weltzin, a USGS scientist and the executive director of something called "The National Phenology Network."

Jake, welcome.

Jake Weltzin: Thank you.

Catherine Puckett: Before anything else, you have to tell us what is phenology.

Jake Weltzin: Well phenology is one of those old-fashioned words that means the study of the timing of life cycle events and that sounds complicated in and of itself, but what we are talking about is things like when flowers bloom or when birds migrate or when animals go into hibernation or the when the leaves change color in the fall. This is phenology, we study it, we see it all the time, and it's a complicated word, but really is a simple process.


Catherine Puckett: Why is phenology useful for studying climate change?

Jake Weltzin: As we say here in our office, timing is everything, and it just seems that the timing of when plants and animals are active across the landscape is a fantastic indicator of climate change. The plants and animals are integrators of their environment.

In other words, all the different things that are happening around them show up in terms of their activity. So, birds are migrating earlier in some cases because of changes in global temperatures or regional temperatures. Flowers are coming up earlier in the spring because of changes in soil moisture or warmer springs or even sometimes you don't have cold winters. So the timing of plant and animal activity is controlled by environmental variables related to climate, and climate change causes changes in the timing of plants and animals.

Catherine Puckett: So sometimes you can get things out of synch. Is that correct?


Jake Weltzin: Well, yes. I think that the complaint is not only things coming earlier. We do have lots of records of flowers coming earlier and birds coming earlier, but there can be these cases where different animals or plants respond differently.

So there are some very good examples of plants that show a very strong response to warming spring whereas some of the animals that depend on those plants for food resources are actually not really changing as much as the plant. They end up with a decoupling or a disconnect in the timing of when migratory birds might arrive and the insects that are living on the flowers that are all coming out earlier.

Catherine Puckett: So that, in turn, could affect reproduction of the birds because they are not getting their food that they normally get and on and on.

Jake Weltzin: We have seen changes in population sizes caused by shifts in phenology. This will be, for example, flowers come out earlier and the bird populations actually crashing as the result of the fact that the resources are no longer there.


Catherine Puckett: Well, Jake, then how can people like us, every day people who love to do things like gardening or watching birds or just getting out and hiking, how can we participate in the USA-NPN?

Jake Weltzin: The National Phenology Network is an organization that is designed to bring in what we called "citizen scientists"—basically volunteers who can help scientists and academics at universities understand how changes are occurring across the entire U.S. There are just not enough scientists at universities to go out and measure what's happening in their environment all across United States, so we rely on we called "citizen scientists" or volunteers to get out there to get us the number of observations across the United States that we need. We'd like a hundred thousand observers around the U.S. who are tracking plant and animal activity.

Catherine Puckett: That's a lot.


Jake Weltzin: It is a lot and what we're trying to do is create protocols so people can go online to our webpage, take a species that interests them, look at the protocols for monitoring. Protocol is a word for "here's how you do it," and then you enter the data online through our new online web interface.

Catherine Puckett: What would be a common species that we might know about? Lilacs?

Jake Weltzin: Lilacs is one common species that actually has been used for 50 years. People have tracked the timing of lilacs and, as part of our network, other people might be more familiar with Ponderosa pines, California poppies, saguaros, maples. So there's a number of common species that should be in your backyard that would be available for you to monitor.

Catherine Puckett: Well, that's really cool because most of us can recognize at least some of those species.

So, Jake, how easy is it to do? It sounds like it's not going to be that difficult—and what do listeners have to do to sign up to become a climate change watcher?


Jake Weltzin: A climate change observer, that's great, when you put it like that, trying to get people outdoors and get people who are interested in participating in climate change science not just reading about it. What you need to do is go to our new webpage,, that's NPN for National Phenology Network, and there is information on how to register, how to make observation, how to enter your data. We're actually working on tools so you can look at your data that you've entered and compare it to everybody else's around the United States who might be tracking lilacs or Ponderosa pine.

Catherine Puckett: Oh, that's really cool. So, how will USA-NPN information be used eventually?

Jake Weltzin: We hope to use its information in several ways. First of all, it gives scientists a very powerful tool to understand how changes in climate are affecting or impacting natural ecological system.


It will help us to understand also how changes in the timing of different organisms will cause what could be in some cases local ecological collapses, where you have species that dependent are upon one another but they are now doing things at different times. It will help us conserve biological diversity.

Catherine Puckett: So you'd be able to perhaps have early warning signs of problems getting ready to occur and could even then let land managers know so that they could then try to avert some disasters.

Jake Weltzin: Exactly. We're in effect building an early warning system. So we are thinking about allergenist plants, too. If you knew when plants were emerging and when it would be coming, you could actually start to manage your own allergens that way with good information. Land managers need information about the timing of when wild fires might occur, and phenology, believe it or not, is tied to the timing of when wild fires occur in the Western United States.


Honey production is another example. Migratory birds and migrations are another example or even for recreation. Wouldn't it be great if there was a web page you could go to where you'll be able to find out real time the color of leaves in the different parts of the state where you usually go for recreation.

Catherine Puckett: You are focusing on plants this year but you are going to be incorporating more animals in the near future, is that correct?

Jake Weltzin: Yes, we're working on building an animal phenology program or animal monitoring program for the United States that should be ready to go next year.

Catherine Puckett: And that will be things like bees and butterflies and that kind of animal?

Jake Weltzin: Yes, exactly. Bees, butterflies, mammals as well. Also working on incorporating aquatic organisms, too, like fishes because there's a lot people out there who are tracking when mayflies come out or other aquatic insects and how that impacts fishing.


Catherine Puckett: So people like fishermen and native plant gardeners or regular gardeners or farmers, all of those are people that you're hoping will sign up for this network?

Jake Weltzin: Yes, we hope to have all of the stakeholders not only be involved in helping track what's going on but then telling us what kind of information they need so that we can help get them tools that they can use to understand their system better.

Catherine Puckett: So, it goes both ways.

Jake Weltzin: We're working on this together.

Catherine Puckett: Can you tell me who some other partners are already in the National Phenology Network?

Jake Weltzin: The U.S. Geological Survey provides base stable support for the NPN.

Catherine Puckett: What does that mean?

Jake Weltzin: That means they are providing the sort of core leadership toward building and keeping the network rolling and moving forward.


But we have some very important and significant partners including the Fish and Wildlife Service who are helping us build our wildlife monitoring program. We have several universities who are working with us including the University of Arizona and the University of Wisconsin and Milwaukee, and we have a number of other federal agencies and state and local agencies as well who are working with us. The Wildlife Society is one very important one.

Catherine Puckett: Well, Jake, thank you very much for being here today and talking to us.

CoreCast is a product of the U.S. Geological Survey, Department of the Interior. We want you all to go outdoors and start tracking.

Thank you.

[Exit Music]


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